PRE-ASSESSMENT OF TRAFFIC MANAGEMENT SYSTEMS

ESTABLISHING A METHODOLOGY FOR PERFORMING COST-BENEFIT ANALYSIS OF ITS INVESTMENTS

Finn Krenk

Danish Road Directorate

The need for pre-assessments

• DRD is expected to justify the investment in ITS C/B

• DRD must prioritize different ITS projects - and ITS projects against traditional measures

• A uniform and consistent methodology is required

• We need to know the effects of different measures

• We want to increase the knowledge of effects, benefits and costs of ITS in Denmark

Scope and background

Scope:• To be able to carry out C/B analyses for ITS• To establish consensus about a common

method

Background:• A general framework for C/B-analyses – MoT• Danish and international studies of costs and

benefits of ITS

Framework for C/B analyses

• Formulate the problem and set up solutions

• Describe reference situation and selected solutions

• Calculate effects in “quantities”

• Calculate value of the effects

• Calculate the net present value, internal interest and benefit/cost ratio

• Describe verbally the not quantified effects

• Arrange the results in a form

Reference situation

Reference situation = ”do nothing scenario”

Costs and benefits: With project - without project

Problems might arise if:

• ITS project in connection with a road work

• ITS project is a part of a new constructed road

• A traffic information service is add-on to existing services

• A TMS is add-on to existing TMS’s

Traffic management and effects

• The most important types of traffic management systems are selected

• Fact sheets are worked out for these

• Guidance are given on which effects should be included in the C/B analysis

• The study describes a number of methods to calculate the effects of ITS applications

Ex.: Fact sheet for Variable speed harmonisation

Type of effect Size

Accidents Reduction in number of accidents with personal injuries on 15-25%. Reduction in number of accidents on 25-28% (1). Reduction in number of accidents on motorways up to 30%

Time gain Average speed reduction on 5-10 km/h on motorways, and totally time gain as a result of lesser accidents

Pollution -

Potential indicators: - Bad traffic flow.- Frequent queues.- Many rear end collisions.- Bad sight.- Many drivers without local knowledge.- Special needs, e.g. road works, special weather conditions, accidents, etc.

Relevance of the parameters

0 = Not relevant

1 = Less relevant

2 = Relevant

3 = Very relevant

Parameters in the C/B analysis

Costs

User effects

Other effects

External effects

The value og being informed

The drivers find it of great value to be informed!

• Traffic information is a big part of ITS systems

• It is important to quantify the drivers value of being informed e.g. by using:- Revealed preference studies- Stated preference studies

• Study from TØI: In Oslo ½ €/trip

• DRD

• Probably best to try different methods

Results for Queuewarning

   

NutidsværdiMarkedspriser

(mio kr.)

Offentlige omkostninger  

Etableringsomkostninger-3,86

Restværdi-

Driftsomkostninger-3,74

Samlet-7,60

  

Brugereffekter 

Tid3,85

Kørselsomk.-

Trafikinformation-

Samlet3,85

  

Eksterne effekter 

Uheld5,50

Andre -

Samlet5,50

  

Øvrige konsekvenser: 

Afgifter0

Skatteforvridning-1,43

Samlet-1,43

  

Samlet nettonutidsværdi:0,31

Intern rente (%)7,8

B/C - faktor1,04

Conclusion

• The general methodology guidelines outlined by the Ministry of Transport and Energy can be applied for evaluating ITS investments

• There is a lack of knowledge of the effectiveness of ITS investments

• There is great uncertainty regarding how drivers valuate traffic

Recommendations for further work

• Monitor international experiences regarding effects and C/B analyses

• Work out evaluation of Danish ITS projects

• Provide data regarding how accidents/incidents effect travelling time

• Analyze how road users value traffic information and services

• Update the method and get it available for the road authorities